Temperature Effects on the Optical Parameters of a Passively Q-Switched Diode-Side Pumped Yb,Er-Laser

Temperature effects on photoluminescence and absorption spectra of the active medium (LGS-DE erbium phosphate glass) and passive Q-switch (MgAl 2 O 4 :Co 2+ crystal) of a diode-side pumped Yb,Er-laser are studied. The obtained data are applied to an analysis of the spectral and energetic characteristics of compact erbium emitters. It is established that the dominant generation channel in the temperature range 233–328 K is the optical transition between lower Stark sublevels of Er 3+ states 4 I 13/2 and 4 I 15/2 (λ = 1532.0–1533.9 nm). A rate-equation system taking into account thermal population of Stark sublevels of states 4 I 13/2 and 4 I 15/2 is proposed to describe the experimental temperature dependence of the threshold absorbed power of the pumping radiation. This system and the lasing threshold enable modeling of Yb,Er-emitter output energetic and temporal characteristics.